Question

find out the retardation if the brakes of car going speed 50 metre per hour and attend rest after moving 250 metre of distance​

Answer 1

Solution :-

As provided :-

Initial velocity = 50 m/s

Final Velocity = 0

Distance covered = 250

Now as Initial velocity , Final Velocity and the distance is provided.

So we can use the motion equation :-

v² = u² + 2aS

So by replacing values :-

0² = (50)² + 2a(250)

→ 0 = 2500 + 500a

→ -2500 = 500a

→a = (-2500) ÷ 500

→a = -5 m/s²

So our acceleration = -5 m/s²

Or retardation

$\Huge{\boxed{\sf{ = 5 \: m/s^2}}}$

Answer 2

Explanation:

According to the question,

Initial velocity (u) = 50m/s

Final velocity (v) = 0 [ as the car comes to rest]

Distance (s) = 250m

Formula Used↓

$\boxed{{v}^{2}={u}^{2}+2as}$

${50}^{2}+2(a)(250m)=0$

2500 + 500a = 0

2500 = -500a

$a = - 5 {m}{ {s}^{2} }$

retardation (r) = - ( acceleration (a) )

retardation (r) = - (-5m/{s}^{2})

$\huge\boxed{retardation=5m/{s}^{2}}$